Electrical Resistivity ofα-Cerium

Electrical-resistivity measurements have been made between 1.5 and 300 °K on $\alpha$-cerium cooled while at pressures of 10 or 18 kbar. Two types of behavior were found: Cerium quenched from 300 to 77 °K showed the presence of a magnetic impurity, possibly clusters of $\beta$-cerium; and cerium which was slowly cooled from room temperature showed no evidence of magnetic behavior. Whereas the "magnetically impure" sample showed a strong $\rho \propto T^2$ dependence at low temperatures, the slowly cooled sample had $\rho \propto T^5$. It is suggested that the magnetic impurity present in previous studies may have prevented the observation of superconductivity in $\alpha$-cerium.